bits function

Set and get bits from binary masks.

Utility functions to access bits from numeric values, for the efficient storage of spatial masks.

bits(object, bit)

bits(object, bit) <-  value

Arguments

• object: a numeric value

• bit: the desired bit

• value: logical value to set bit to

Details

uses 32-bit integers, so we can (easily) access 31 binary matrices in each numeric matrix. This is very useful for storing long time-series of spatial masks, required for track-location estimation from archival tags.

Returns

A numeric object with the given bit set, or a logical value designating the status of the given bit.

Author(s)

Michael D. Sumner

Note

The 32nd bit is harder to access, so we ignore it.

See Also

See Also get.mask for a higher level access of a mask object

Examples

a <- 1L
bits(a, 0)  ## 1
bits(a, 2) <- 1
a   # 5